Materials Science Forum Vols. 505-507

Abstract: In this paper, a shaving cutter with serration and a pre-designed relief portion manufactured by a hob cutter was designed. Due to the non-conventional manufacturing process, standard manufacturing problems were avoided and the production efficiency was enhanced as was the stiffness of the shaving cutter. Two solid models of the shaving cutter, one with the novel relief portion and the other a relief hole, were set up for stress analysis using the finite element method. The models confirmed that the shaving cutter with the novel relief portion had a higher stiffness compared to that with a relief hole in the presence of serration.

Abstract: The goal of this research is to develop a design and optimization methodology for the mechatronic modules of machine tools by treating all important characteristics from all involved engineering domains in one single process. In this study, a mechatronic system of machine tools was broken into a structure and control two-level systems. In the first stage for structure design process, the Pro/E was used to build up the 3D models and the AnSys was employed to design the mechanical structure and select the optimal components for the machine tools. Next, in the control design process, a common controller type was designed by MATLAB in this stage. Then, three important parameters were established for the machine tools design to achieve the overall system performance.

Abstract: Ultrasonic guided wave has been widely used for the pipe inspection. The conventional method is to use piezoelectric transducers that should be contacted to the target surface. However, in order to automatically inspect pipes in the manufacturing stage, non-contact inspections are strongly required. In this paper, we propose a new non-contact method for the automation of pipe inspection, which generates the ultrasonic guided wave by laser and receives by air-coupled transducer. Also we have developed a rotational canning system to show the inspection result as a 2-D image, which makes the operator find out defects easily. Then, in practical applications of guided wave techniques, it is preferred to generate and detect a single or less dispersive mode. So this paper considers the enhancement of mode-selectivity, where a laser beam illuminated through arrayed line slits is used as the transmitter and the air-coupled transducer is used as the receiver. The line arrayed laser illumination is a wavelength matching technique that can generate only a few modes. The air-coupled transducer detects the leaky wave of the propagated guided wave, and by tuning its detection angle we can detect the selected single mode. This method can generate and receive the guided wave of a specific mode, which makes the interpretation of received signal clearer and resultantly improves the accuracy of inspection. The proposed method was applied to the stainless pipe specimen with artificial defects and its inspection performance was verified. The experimental results showed that the fundamental axial-longitudinal mode was dominantly generated and received, and the location and the size of pipe defects could be displayed well in the 2 dimensional scanning images in real time.

Abstract: In this paper, generated path control of an elastic linkage is first controlled using a five-bar linkage with a variable length crank. The theoretical foundation of precision control of generated path of elastic linkage is formed by application of an optimal method. Experimental study of the generated path of linkages is made on the basis of the theoretical study. The experimental results agree with the theoretical one essentially and prove the feasibility of the theory.

Abstract: The traditional design and analysis method for the eccentric involutes gears transmission has model error. Some important parameters, such as minimum geometrical center distance and eccentricity, are not calculated accurately. The differential equation of eccentric involute gears transmission is established on account of the geometrical relationship of eccentric involute gears transmission. A calculating method of the geometrical center distance and eccentricity are derived. The relationship between the minimum geometrical center distance or maximum transmission ratio and initial meshing angle and eccentricity are analyzed. The minimum geometrical center distance and eccentricity are fitted by polynomial. The analysis and design can be completed fast and accurately by using polynomial fitting formals, so the process of analysis and design are simplified.

Abstract: This paper proposes a method of geometry modeling for indexing cam mechanism by using screw theory and exponential product formula. Kinematic analysis based on screw theory is introduced firstly. Then, method to model surface of indexing cams is presented when screw theory and exponential product formula are applied. The paper gives examples to obtain the geometry models of roller gear cam, barrel indexing cam and parallel indexing cam. Our work suggests that this method can avoid the burdensome work on building coordinate systems, transformation matrixes and understanding on the mechanism. Moreover, this method can be used to innovate and design new types of indexing mechanism.

Abstract: When manufacturing electric motors, the armature must be carefully balanced before the motor is assembled to ensure that the motor remains within specified vibration limits when in operation. This study develops a novel scheme for the automatic balancing of motor armatures. In the proposed scheme, a Kalman filter is employed to make the milling system adaptive to the wear conditions. The balancing scheme is validated by performing a series of experiments using automobile starting motor armatures.

Abstract: Planetary gear trains can be used as the transmission systems with high reduction ratio for power machinery. The purpose of this paper is to propose an algorithm for the kinematic design of planetary gear trains with high reduction ratio. Based on the concept of train value equation, we propose a new representation to present the kinematic relationship of the members of the train loop. According to this representation graph, we propose an efficient algorithm for the kinematic design of planetary gear trains with high reduction ratio. Three design examples are designed to illustrate the design algorithm. Based on the proposed algorithm, all planetary gear trains with high reduction ratio can be synthesized.

Abstract: An Intelligent Tool Post (ITP) used in lathe is proposed in this study. ITP is designed from the basis of two different cutting force characteristics produced from abnormal cutting generated by tool crashing workpiece and from normal cutting. ITP is capable of sensing and distinguishing the normal cutting signals from the abnormal ones. During normal cutting, ITP is able to resist the cutting torque and continue the cutting. As abnormal cutting occurs, the tool would move away from the workpiece without any damage. The equations for design and operation have been established. With the threshold and the design equation, one can design appropriate ITP. The threshold can be calculated and set up by the operating equation and the cutting conditions. Furthermore, Taguchi method was employed to conduct the experiments and analyze the experimental results. The results showed that the ITP’s functions met the design requirements completely.

Abstract: In this paper, a nonlinear recursive method for the dynamic and kinematic analysis of a closed-loop flexible manufacturing system is presented. The kinematic and dynamic models are developed using absolute reference, joint relative, and elastic coordinates as well as joint reaction forces. This recursive method leads to a system of loosely coupled equations of motion. In a closed-loop manufacturing system, cuts are made at selected secondary joints in order to form spanning tree structures. Compatibility conditions and reaction force relationships at the secondary joints are adjoined to the equations of open-loop manufacturing systems in order to form closed-loop kinematic and dynamic equations. Using the sparse matrix structure of these equations and the fact that the joint reaction forces associated with elastic degrees of freedom do not represent independent variables, a method for decoupling the joint and elastic accelerations is developed. Unlike existing recursive formulations, this method does not require inverse or factorization of large nonlinear matrices. The application of nonlinear recursive method in kinematic and dynamic analysis of closed-loop manufacturing systems is also discussed in this paper. The use of the numerical algorithm developed in this investigation is illustrated by a closed-loop flexible four-bar mechanism.